N55 FBO, Proturn + aFe Stg 2 Dyno

bNks334 · 09-06-2016, 03:31 PM

Quote:

Originally Posted by EB89

Yeah hanging out for MHD to release N55 support.

Will we need to upgrade our diverter valves? Someone said above they are only designed to hold 8-10 psi

It's a rubber diaphragm that might rupture or stick open when holding greater than stock boost causing boost leaks and turbo lag since boost is dumped. Lots more info available on why dv+ is a good mod on the vw forums since it's actually a popular mod over there when tuning. Their cars use almost the same diaphram as ours... dv+ replaces the rubber with a brass piston.

Only problem is it's attached to the turbo and hard to get to without removing the water pump.

omgboost · 09-07-2016, 09:45 AM

Quote:

Originally Posted by bNks334

Only problem is it's attached to the turbo and hard to get to without removing the water pump.

If I replace the electronic water pump when it fails, I'm thinking it would be a good time to replace the DV with the DV+. From the looks of it, it looks like all the N55 DV are the same so it should work for my X5.

houtan · 09-07-2016, 06:28 PM

Quote:

Originally Posted by bNks334

It's a rubber diaphragm that might rupture or stick open when holding greater than stock boost causing boost leaks and turbo lag since boost is dumped. Lots more info available on why dv+ is a good mod on the vw forums since it's actually a popular mod over there when tuning. Their cars use almost the same diaphram as ours... dv+ replaces the rubber with a brass piston.

Only problem is it's attached to the turbo and hard to get to without removing the water pump.

What is your logic on upgrading the dv on the stock turbo. Who cares if it's rubber when it works fine on the stock turbo. I have never heard of the stock dv limiting the amount of boost the stock turbo can hold. Do you think since you are running an upgraded diverter, that you can hold more boost in the upper rev band compared to a stock diverter valve? Just trying to understand what you have seen that makes you think it's worthwhile on the N55.

bNks334 · 09-07-2016, 08:52 PM

Basically to answer your question would be to rehash what I've already said: here a quick Google link http://www.golfmk6.com/forums/showthread.php?t=66691

I brought the diverter valve upgrade up for this exact reason. I don't really see any other BMW engines utilizing this diaphram style diverter valave. Hence why I pointed to vw/audi which pretty much all use it. On those cars the diaphragm has been revised over the years to add a basket to protect the rubber diaphragm. It's not as easy for us to replace .This is also probably why you haven't heard much about upgrading it over here. Since it's attached to the turbo it's just written off.

I don't think there is any question there is room for improvement above 17-18psi. Wish op would post a log so I can compare to it. There is most definetly a massive improvement to throttle response since the dv+ can actually hold any amount to of boost you ask it to whereas the stock diaphram bleeds boost at high psi.

aaron_ · 09-08-2016, 10:11 PM

my DV+ is going in tomorrow. wooohooooo. its only a cheap mod. why not do it. especially if your water pump is already out

yippy · 09-14-2016, 04:38 PM

Quote:

Originally Posted by bNks334

Go on Cobbs website. They list every protuner. There are tons of options in my area (NY).

PTF and wedge aren't the holy grail of n55 tuning. I have 10 different wedge tunes on my access port and my car misfires like crazy with every single one of them.

Waiting on mhd makes sense since vanos plays such a key role in managing the relationship between torque and hp (hence why the power curves of our "tuned" cars looks like shit). N55s don't have access to that table from what I understand. Does the public xdf have vanos mapped? If so, I might have to teach myself how to bench flash and do this shit myself.

Thanks a lot.
Mhd was created near me. I think, I didn't wait so long...

I've one more little question:
Needs the N55 an upgrade N20 Sensor or is this not necessary?
And is the answer yes, where can I buy this?
I'll upgrade my turbo...

With the best
Yippy

Cory S · 09-14-2016, 06:03 PM

Quote:

Originally Posted by yippy

Thanks a lot.
Mhd was created near me. I think, I didn't wait so long...

I've one more little question:
Needs the N55 an upgrade N20 Sensor or is this not necessary?
And is the answer yes, where can I buy this?
I'll upgrade my turbo...

With the best
Yippy

Purchased mine from EBay for $79.00. OEM N20 3.5 bar TMAP

DrRobert · 09-15-2016, 01:19 AM

Quote:

Originally Posted by Cory S

Purchased mine from EBay for $79.00. OEM N20 3.5 bar TMAP

I thought that only helped if you are using JB4 for boost control.

Cory S · 09-15-2016, 08:06 AM

Quote:

Originally Posted by DrRobert

I thought that only helped if you are using JB4 for boost control.

I am

bNks334 · 09-16-2016, 09:11 AM

After pouring through logs it looks like my car runs rich in 4th gear in certain situations.

Could this be a map adding fuel to protect a non-existent catalytic converter when things start getting hot? Not sure how that works, but I know the stock car does add fuel at high load to protect the cats.

bNks334 · 09-16-2016, 03:28 PM

Quote:

Originally Posted by TGNY 335

it seems to be an issue with the car switching to another table. fixes are going to be test for this.

Alright, makes sense then.

Also, I reviewed mass airflow logs. You're right that this turbo taps out at about 330g/s or 44lb/min @ around ~4900 rpms (440 crank HP). After that, the turbo can't keep up with requested airflow and manifold pressure (psi) drops.

I think a comparable turbo spec sheet is the BW-6258: http://www.full-race.com/store/turbo...258-turbo.html

Looks like this car would need a turbo that can blow closer to 450-500g/s of airflow to maintain 20psi to redline. Unfortunately, a larger turbo is a compromise to low/midrange power.

Cory S · 09-16-2016, 03:41 PM

Quote:

Originally Posted by bNks334

Alright, makes sense then.

Also, I reviewed mass airflow logs. You're right that this turbo taps out at about 330g/s or 44lb/min @ around ~4900 rpms (440 crank HP). After that, the turbo can't keep up with requested airflow and manifold pressure (psi) drops.

I think a comparable turbo spec sheet is the BW-6258: http://www.full-race.com/store/turbo...258-turbo.html

Looks like this car would need a turbo that can blow closer to 450-500g/s of airflow to maintain 20psi to redline. Unfortunately, a larger turbo is a compromise to low/midrange power.

The PS2 stills bellows out mid-range power, but the spool up delay just kills any throttle response down low.

DrRobert · 09-17-2016, 12:09 PM

Quote:

Originally Posted by Cory S

I am

Thanks for clarifying that!

09-07-2016, 08:52 PM	#48
bNks334 Major 429 Rep 957 Posts Drives: '11 135i (N55) Join Date: May 2014 Location: New York iTrader: (1)	Basically to answer your question would be to rehash what I've already said: here a quick Google link http://www.golfmk6.com/forums/showthread.php?t=66691 I brought the diverter valve upgrade up for this exact reason. I don't really see any other BMW engines utilizing this diaphram style diverter valave. Hence why I pointed to vw/audi which pretty much all use it. On those cars the diaphragm has been revised over the years to add a basket to protect the rubber diaphragm. It's not as easy for us to replace .This is also probably why you haven't heard much about upgrading it over here. Since it's attached to the turbo it's just written off. I don't think there is any question there is room for improvement above 17-18psi. Wish op would post a log so I can compare to it. There is most definetly a massive improvement to throttle response since the dv+ can actually hold any amount to of boost you ask it to whereas the stock diaphram bleeds boost at high psi. Last edited by bNks334; 09-11-2016 at 10:10 AM..
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09-08-2016, 10:11 PM	#49
aaron_ Captain 96 Rep 671 Posts Drives: E93 335i LCI Join Date: Dec 2015 Location: Sydney iTrader: (0)	my DV+ is going in tomorrow. wooohooooo. its only a cheap mod. why not do it. especially if your water pump is already out
	Appreciate 0 Quote

09-16-2016, 09:11 AM	#54
bNks334 Major 429 Rep 957 Posts Drives: '11 135i (N55) Join Date: May 2014 Location: New York iTrader: (1)	After pouring through logs it looks like my car runs rich in 4th gear in certain situations. Could this be a map adding fuel to protect a non-existent catalytic converter when things start getting hot? Not sure how that works, but I know the stock car does add fuel at high load to protect the cats.
	Appreciate 0 Quote